Lifting mechanism with support function

ABSTRACT

A lifting mechanism with support function includes pivot arm component composed of a first pivot arm and a second pivot arm parallel to each other. The first and second pivot arms each have two ends thereof pivotally connected to a fixation joint and an active joint respectively, and the pivotally connected points connecting the first link, the second link, the fixation joint and the active joint jointly define a parallelogram. One end of an adjustable damper pivotally connects to the pivot arm component, and the other end thereof pivotally connects to the fixation joint or the active joint via an adjustment component, so the adjustable damper can be controlled to extend/retract or be locked; the adjustment component includes a first pivot seat capable of relatively moving to change the support angle of the adjustable damper to adjust the damping support force provided from the adjustable damper.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation-in-part of U.S. application Ser. No. 14/717,252,filed on May 20, 2015, which is incorporated herewith by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a lifting mechanism with supportfunction, in particular to a lifting mechanism which can be controlledto vertically extend/retract and revolve, and can be controlled toadjust its support.

2. Description of Related Art

An office chair with a gas cylinder is an example for devices that havea simple lifting mechanism that allows easy altitudinal adjustment. In aconventional office chair, a seat is connected to a caster-equipped basethrough a pneumatic device. The pneumatic device is operated by a switchto place the seat at different altitudes that meets various needs inuse. However, such a structure can only realize altitudinal adjustment,and does not support displacement in other directions (such asforward/backward or leftward/right displacement), making its uselimited.

There is also a mechanism having a post (or a plurality of links)connected to a loading platform (for receiving a keyboard and a monitor)through at least one pneumatic element (such as a gas cylinder). It issuch designed that the support force forms the pneumatic element isslightly greater than the overall weight of the loading platform (plusthe keyboard and the monitor), so that after the loading platform (plusthe keyboard and the monitor) is adjusted to a desired position, it isheld at that position and a balanced posture of the whole mechanism isformed. While this structure allows altitudinal and positionaladjustment depending on the characteristics of the used post (or theplural links), the balance between the loading platform and thepneumatic element tends to be broken by external force (such as thatfrom a user's palms pressing loading platform when operating a keyboardplaced on the) in practical use. When the user operates the mechanism,the loading platform gradually descends; for the reason, the user shoulduse his arm and hand to lift the loading platform, which will result inpotential mental pressure; besides, the user may suffer from tendonitisif using the mechanism for a long time, which making it inconvenient touse.

In view of the shortcomings of the known lifting devices, the inventorof the present invention has made improvements thereto and creates thepresent invention.

SUMMARY OF THE INVENTION

The present invention is to use a pivot arm component to provide alinkage supporting between a preset loading component and a loadingplatform set, and a damping positioning mechanism is located between thelinkage and the loading component, so that the damping positioningmechanism that can be controlled to extend or retract, and canautomatically position the linked structure after operation, the loadingplatform set can be well positioned at its post-adjustment position.

The present invention is to make the damping positioning mechanism andthe pivot arm component arranged between different loading componentsand loading platform sets as needed, so as to improve the application ofthe device and add value to the final products using the same.

The present invention can form a parallelogram by the linkage of thepivot arm component, the fixation joint of the loading component and theactive joint of the loading platform set, so that the loading platformset can be freely moved upward/downward, forward/backward, orrightward/leftward in a certain angular area, while remaininghorizontal, thereby providing convenient use.

The active joint and the fixation joint of the present invention canfurther work with a revolver so that the loading platform set is allowedto perform rotation in both directions in addition to relativemovements, thereby improving its convenience in use.

Besides, the present invention is further to provide an adjustmentcomponent to the front end of the adjustment damper, so that the frontend of the adjustment damper can be located at the first pivot seat; thesupport angle of the adjustment damper can be changed by adjusting theposition of the first pivot seat so as to further change the adjustmentdamper's damping support forse provided for the loading platform set; inthis way, the user can adjust the adjustment damper to the proper angleaccording to the loading weight so as to achieve balance and decreasethe burden of the descending/ascending operation, which can increase theconvenience.

To achieve the foregoing objectives and effects, the present inventionimplements the following technical scheme: a fixation joint; an activejoint, connecting to a loading platform set; a pivot arm componentinstalled between the fixation joint and the active joint, including afirst pivot arm and a second pivot arm, wherein one end of the firstpivot arm and one end of the second pivot arm are pivotally connected tothe fixation joint, and the other end of the first pivot arm and theother end of the second pivot arm are pivotally connected to the activejoint, the relation position of the first pivot arm, the second pivotarm, the pivot shaft of the fixation joint and the pivot shaft of theactive joint substantially form a parallelogram, whereby the first pivotarm and the second pivot arm are able to pivot within a certain range,and the active joint descends or ascends relative to the fixation joint;a damping positioning mechanism, including an adjustable damper and aswitch, wherein one end of the adjustable damper is installed on thepivot arm component, and the other end of the adjustable damper connectsto the fixation joint or the active joint via an adjustment component;and the adjustable damper is connected to the switch via a control cord,and able to be controlled by the switch to be the adjustable status orthe locked status; the adjustable damper is able to extend or retractand provides some damping support forse during the adjustable status, sothe active joint is able to pivot relative to the fixation joint via thepivot arm component; the adjustable damper is able to fix the anglebetween the pivot arm component, and the active joint or fixation jointduring the locked status for positioning; further, the adjustmentcomponent includes a first pivot seat capable of relatively moving, andthe end of the adjustable damper pivotally connects to the first pivotseat, and the support angle of the adjustable damper is able to bechanged by adjusting the position of the first pivot seat so as toadjust the damping support forse provided from the adjustable damper tosupport the loading platform set.

Thereby, the damper can provide proper damping support forse, and cansue the adjustment component to achieve balance in accordance with thetotal load born by the loading platform set. In addition, the switchcontrols the damper to extend or retract or get locked from extending orretracting. A user can easily move the loading platform set by pressingthe switch an applying a minor force to reposition the loading platformset to a desired position. During the movement, the user does not needto hold and bear the loading platform set, and when moved to the desiredposition, the loading platform set can be easily positioned by theuser's releasing the switch which locks the damper. The loading platformset is thus secured from being moved under external force, therebysignificantly improving convenience in use.

In the configuration discussed above, the end of the adjustable damperconnects to the first pivot arm or the second pivot arm via a secondpivot seat.

In the configuration discussed above, the adjustment component furtherincludes a lead screw, and the first pivot seat is mounted on the leadscrew; when the lead screw revolves, the first pivot seat is able tomove toward to lead screw.

In the configuration discussed above, the adjustment component furtherconnects to an indicator mechanism for displaying the measurement of thedamping support forse provided for the loading platform set.

In the configuration discussed above, the indicator mechanism includes agear set connecting to the lead screw; the gear set is able to revolveby being linked to the lead screw, and display the measurement of thedamping support forse provided for the loading platform set via anopening externally exposed to outside.

In the configuration discussed above, the indicator mechanism includesan indicator connecting to the first pivot seat, and the indicator isable to move with the first pivot seat, and display the measurement ofthe damping support forse provided for the loading platform set via afront end protruding outward.

In the configuration discussed above, the first pivot arm and the secondpivot arm pivotally connect to an inner position and an outer positionrespectively via a plurality of shaft sleeves; the first pivot arm andthe second pivot arm have lateral walls capable of overlapping with eachother, whereby the lateral walls are able to partially overlap with eachother when the first pivot arm and the second pivot arm are inoperation.

In the configuration discussed above, wherein the active joint furtherincludes a connection board and a locking sheet, and the first pivot armand the second pivot arm are pivotally installed between the connectionboard and the locking sheet.

In the configuration discussed above, the locking sheet is fixed on theconnection board via three points substantially form a triangle; thefirst pivot arm and the second pivot arm respectively pivotally connectto one of the three points.

In the configuration discussed above, the fixation joint is fixed at abase, a clamping base or a revolver.

In the configuration discussed above, the active joint connects to aplatform or a pivot holder.

The invention as well as a preferred mode of use, further objectives andadvantages thereof will be best understood by reference to the followingdetailed description of illustrative embodiments when read inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B are schematic views of an application mode of thepresent invention.

FIG. 2 is a 3D structure schematic view of a first embodiment of thepresent invention.

FIG. 3 is a status schematic side view of the first embodiment of thepresent invention, showing that it is positioned at a high position.

FIG. 4 is a status schematic view of the first embodiment of the presentinvention, showing that it is positioned at a low position.

FIG. 5 and FIG. 6 are schematic views of the first embodiment with anadjustment component of the present invention, showing it is positionedat the low position and the high position respectively.

FIG. 7 is a 3D structure schematic of a second embodiment of the presentinvention.

FIG. 8 is a structure schematic view of the main structure of a liftingmechanism with support function of the second embodiment of the presentinvention.

FIG. 9 and FIG. 10 are local perspective views of the lifting mechanismwith support function of the second embodiment of the present invention.

FIG. 11 is an operation schematic view of an adjustment component of thesecond embodiment of the present invention.

FIG. 12 and FIG. 13 are status schematic views of the second embodimentof the present invention, showing it is positioned at the low positionand the high position respectively.

FIG. 14 is an assembly schematic view of a fixation joint and a clampingbase of the second embodiment of the present invention.

FIG. 15 is a 3D structure schematic of a third embodiment of the presentinvention.

FIG. 16 is an operation schematic view of an adjustment component of thethird embodiment of the present invention.

FIG. 17 and FIG. 18 are status schematic views of the third embodimentof the present invention, showing it is positioned at the low positionand the high position respectively.

FIG. 19 is a 3D structure schematic view of a fourth embodiment of thepresent invention.

FIG. 20 is a status schematic side view of the fourth embodiment of thepresent invention, showing that it is positioned at a low position.

FIG. 21 is a status schematic side view of the fourth embodiment of thepresent invention, showing that the second loading platform is foldedupward.

FIG. 22 is a status schematic side view of the fourth embodiment of thepresent invention, showing that it is positioned at a high position.

FIG. 23 is a top view of the fourth embodiment of the present invention.

FIG. 24 is another top view of the fourth embodiment of the presentinvention, showing that it sways to one side.

FIG. 25 is a structure schematic view of the lifting mechanism withsupport function of the fourth embodiment of the present invention.

FIG. 26 is a local amplifying perspective view of FIG. 25.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is majorly based on the pivot mechanism formed bytwo parallel pivot arms; the present invention can have many modesaccording to actual applications, but all of which are based on the samebasic structure and operation principle. As shown in FIG. 1A and FIG.1B, the pivot arm component P3 is pivotally installed between a fixationjoint P11 and an active joint P211. The fixation joint P11 is usuallythe fixation end for forming a fixation support point; on the contrary,the active joint P211 is usually the active end for connecting to aplatform capable of ascending/descending. Besides, the pivot armcomponent P3 has a first pivot arm P31 and a second pivot arm P32parallel to each other, and the pivot shaft connection line between bothends of which, and the fixation joint P11 and the active joint P211 canjust from a parallelogram, such that when the first and second pivotarms P31, P32 revolve, the active joint P211 can keep a constant angledisplacement, and the platform connected to which can also horizontallyascend or descend. As shown in FIG. 1A, the pivotal connection positionof the first and second pivot arms P31, P32 is slope (the included angleof the pivot shaft connection line of them and the horizontal plane isabout) 45°, so they are suitable for 0˜90° ascending/descendingoperations. As shown in FIG. 1B, the pivotal connection position of thefirst and second pivot arms P31, P32 is vertical, so they are suitablefor −45˜45° ascending/descending operations. In other words, manyapplication modes can be provided according to the relation position ofthe first and second pivot arms P31, P32. FIG. 1A and FIG. 1B just showthe preferred application modes of the present invention, which have thesame structure of the pivot arm component P3 and the pivot operationprinciple.

Referring to FIGS. 2 and 3, according to the first embodiment of thelifting mechanism with support function of the present invention, thedisclosed mechanism comprises: a loading component 1, a loading platformset 2, a pivot arm component 3, and a damping positioning mechanism 4.Therein, the loading component 1 is locally provided with a fixationjoint 11, and the fixation joint 11 contains therein a first pivot seat12.

In the present embodiment, the loading component 1 is a flat base, whichcan be stably placed on a predetermined plane, and the joint 11 and thefirst pivot seat 120 are installed on the base.

The loading platform set 2 is composed of a first loading platform 21and a second loading platform 22. The first and second loading platform21, 22 are connected to each other by means of an extension support 23,so that the first and second loading platforms 21, 22 are mutuallyparallel and have an altitudinal difference therebetween. The firstloading platform 21 is provided with an active joint 211.

The pivot arm component 3 is composed of a first pivot arm 31 and asecond pivot arm 32 that are parallel to each other. The first andsecond pivot arms 31, 32 each have one end pivotally connected to thefixation joint 11 of the loading component 1 by means of a pin A or B,and each have an opposite end pivotally connected to the active joint211 of the loading platform set 2 by means of a pin C or D, so that thecorresponding ends of the pins A, B, C and D jointly define aparallelogram. The first pivot arm 31 is provided with a second pivotseat 311.

In the present embodiment shown in the drawings, the first and secondpivot arms 31, 32 are telescoped, so as to eliminate the risk of mutualinterference therebetween in practical operation. In general, the firstand second pivot arms 31. 32 can have the lateral walls capable ofoverlapping with each other; shaft sleeves can be installed on the pivotshafts, so the lateral walls of the first and second pivot arms 31, 32can be located the inner side and the outer side respectively, and willnot interfere with each other during the pivot process; besides, thelateral walls can keep a partially overlapping status during the pivotoperation, such that the fingers of the user will not be hurt because ofbeing clamped by the arms.

The damping positioning mechanism 4 is composed of an adjustable damper41 (that may be a gas cylinder with locking function) and a switch 42.The adjustment damper 41 is pivotally connected between the second pivotseat 311 of the first pivot arm 31 and the first pivot seat 120 of theloading component 1, and the adjustable damper 41 is connected to theswitch 42 by means of a control cord 43. The switch 42 may be placed atone side of the second loading platform 22 and may have an operatablepaddle 421. When the paddle 421 is operated, the switch 42 controls theadjustable damper 41 to allow it to extend or retract in response to anexternal force. When the paddle 421 is released, the adjustable damper41 locks itself from extending and retracting.

Referring to FIG. 4, according to the first embodiment of the presentinvention, during the positional adjustment, when the paddle 421 isoperated, the second loading platform 22 can be pushed or pressed at thesame time by a user, so that the loading platform set 2 drives the firstand second pivot arms 31, 32 to rotate relatively. Throughout theprocess of the rotation, the imaginary line connecting the pins C and Dremains parallel to the imaginary line connecting the pins A and B(holding the parallelogram), so the loading platform set 2 is restrictedto move forward/backward and upward/downward while remaining parallel tothe loading component 1. With the pivotal movement of the first pivotarm 31, the adjustable damper 41 receives force and is driven to extendor retract.

When the loading platform set 2 moves to a desire position, the user mayrelease the paddle 421, so that the adjustable damper 41 is locked andprevented from extending and retracting, making the loading platform set2 positioned. Thereby, even if the loading platform set 2 (the first andsecond loading platforms 21 and 22) receives external force (such asthat from a user's palms pressing the second loading platform 22 whenoperating a keyboard placed on the second loading platform 22), it isunlikely to have unintentional displacement, making its use moreconvenient.

In general, when the user operates the paddle 421, the adjustable damper41 usually generates certain damping support forse to the loadingplatform set 2 so as to support the weight on the loading platform set2, such that the force for lifting or pressing down provided by the usercan be reduced; thus, the user can easily operate the loading platformset 2 to ascend or descend. Moreover, as shown in FIGS. 5 and 6, theadjustable damper 41 can further connect to the loading component 1 orthe fixation joint 11 via an adjustment component 12. The adjustmentcomponent 12 majorly includes a first pivot seat 120 and a lead screw121. The lead screw 121 is fixed at the loading component 1 and thefirst pivot seat 120 is installed on the lead screw 121. By means of therotation of the lead screw 121, the first pivot seat can have relativedisplacement; when the first pivot seat 121 moves, the support angle ofthe adjustable damper 41 can be changed, so its damping support forse tothe loading platform set 2 can be adjusted. Therefore, the use canadjust the damping support forse according to the load of the loadingplatform set 2 to achieve balance between them. In this way, when theuser operates the paddle 421, the user has no need to lift (the table istoo heavy) or press down (the table is too light), such that the use canperform the ascending/descending operations without difficulty.

In a feasible embodiment, the adjustment component 12 can furtherconnect to an indicator mechanism for showing the adjustable damper 41'sdamping support forse to the loading platform set 2 as the indicator forthe user to adjust. Moreover, the pivotal connection position of theactive joint 211, and the first and second pivot arms can be furtherinstalled with a locking sheet 213 with three fixation points, which canconcentrate the stress and fix the relative position of them. For thereason, the loading platform set 2 will not be unstable because the armsintersect with each other or due to the stress difference. The followingembodiments will provide more detailed description about the technicalfeatures of the indicator mechanism and the locking sheet.

Please refer to FIG. 7˜FIG. 11, which shows the second embodiment of thelifting mechanism with support function of the present invention; themechanism also includes a loading component 1′, a loading platform set2′, a pivot arm component 3′ and a damping positioning mechanism 4, etc.The major difference is that the shape of the pivot arm component 3′ ischanged, and the loading component 1′ has a clamping base 14′ capable ofbeing fixed at a default plane or carrier.

More specifically, the loading component 1′ is connected to a fixationjoint 11′ and the loading platform set 2′ is connected to an activejoint 211′. The pivot arm component 3′ has a first pivot arm 31′ and asecond pivot arm 32′ parallel to each other. One end of the first andsecond pivot arms 31′, 32′ is pivotally connected to the fixation joint11′ and the other end thereof is pivotally connected to the active joint211′; the positions of the pivotal connection shafts can form aparallelogram.

In the embodiment, the loading component 1′ include a clamping base 14′and a fixation joint 11′; please also refer to FIG. 14, the clampingbase 14′ can clamp and be fixed at a default object, and have aplurality of arranged locking connection holes 140′, such that thefixation joint 11′ can connect to the proper position of the clampingbase 14′ to increase its usability. The loading platform set 2′ includesa first loading platform 21′, a second loading platform 22′ and anextension holder 23′ connecting them with each other, so the first andthe second loading platforms 21′, 22′ can be parallel to each other, andhave a height difference; the active joint 211′ can stably connect tothe bottom of the first loading platform 211′.

The first and second pivot arms 31′, 32′ of the pivot arm component 3′are arranged adjacent to each other and sleeved with each other to forman inner hollow space; as shown in FIGS. 8 and 9, the inner sides or theouter sides of the pivotal connection shafts of the first and the secondpivot arms 31′, 32′ are installed with a plurality of shaft sleeves 33′,such that the lateral walls 310′, 320′ of the first and second pivotarms 31′, 32′ can overlap with each other without interfering with eachother during the pivot operation. Further, the lateral walls 310′, 320′thereof can keep partially overlapping with each other during the pivotoperation, which can prevent foreign objects from entering inside thefirst and the second pivot arms 31′, 32′ in order to prevent the userfrom being accidentally hurt because of being clamped by them. Moreover,so as to increase the stability of the mechanism, a locking sheet 213′can be further installed on the pivotal connection position of theactive joint 211′, and the first and second pivot arms 31′, 32′. Thelocking sheet 213′ are fixed at connection board 212′ of the activejoint 211′ by using three pins as the fixation points. The first andsecond pivot arms 31′, 32′ are pivotally installed between theconnection board 212′ and the locking sheet 213′, and located at two ofthe fixation points respectively, such that the stress can beconcentrated to fix the relative position; in this way, the loadingplatform set 2′ will not be unstable because the pivot arms intersectwith each other or the stress is changed.

Please refer to FIG. 10˜FIG. 13, the damping positioning mechanism 4′mainly includes an adjustable damper 41′ and a switch 42′; morespecifically, one end of the adjustable damper 41′ pivotally connects tothe second pivot seat 311′ of the first pivot arm 31′, and the other endthereof pivotally connects to the adjustment component 12′ of thefixation joint 11′; further, the adjustable damper 42′ can connect tothe switch 42′ via a control cord 43′. The adjustment component 12′majorly includes a first pivot seat 120′ capable of relatively movingand a lead screw 121′ capable of driving the first pivot seat 120′. Thefirst pivot seat 120′ is installed on the lead screw 121′, and the leadscrew 121′ can be installed in a slot way 122′. The lead screw 121′ canrevolve to drive the first pivot seat 120′ to move toward the lead screw121′. The adjustable damper 41′ pivotally connects to the first pivotseat 120′, so the support angle of the adjustable damper 41′ can bechanged (as shown in FIG. 11) when the first pivot seat 120′ relativelymoves so as to change the damping support forse of adjustable damper 41′provided for the loading platform set 2′.

When actually using the mechanism, the user can touch the switch 42′ tomake the adjustable damper 41′ be the adjustable status; then, the usercan operate the loading platform set 2′ to drive the first and secondpivot arms 31′, 32′ to relatively revolve. Besides, during the pivotprocess, the parallelogram formed by the arrangement of the pivot shaftscan make the loading platform set 2′ horizontally ascend or descend (asshown in FIG. 12 and FIG. 13). After reaching the proper position, theuser can release the switch 42′ to lock the adjustable damper 41′, sothe loading platform set 2′ can be well positioned. In addition, duringthe usage process, the user can adjust the lead screw 121′ according tothe requirements in order to make the damping support forse provided forthe loading platform set 2′ reach balance with the load. In this way,when performing the ascending/descending operations, the user has noneed to apply the lifting force (the table is too heave) orpressing-down force (the table is too light), so the user can easily andconveniently operate the mechanism.

In a feasible embodiment, the adjustment component 12′ can connect to anindicator mechanism 13′ so as to show the corresponding damping supportforse for the user to observe and adjust. In the embodiment, as shown inFIG. 10, the indicator mechanism 13′ majorly includes a gear set 130′composed of a first gear 131′, a second gear 132′ and a third gear 133′.The lateral side of the third gear 133′ can have a force meter, andwhich can expose from an opening 110′ at the relative position for theuser to perform the adjustment according the shown force (correspondingto the load).

Please refer to FIG. 15˜FIG. 18, which show the third embodiment of thelifting mechanism with support function of the present invention; themajor changes are the shape of the pivot arm component 3″ and thepivotal connection position of the adjustable damper 41″. As shown inthese figures, the main structure includes a loading component 1″, aloading platform set 2″, a pivot arm component 3″ and a dampingpositioning mechanism 4″.

The loading component 1″ is basically a horizontal frame, which can beinstalled on and fixed at the surface of a common table, or a defaultcarrier; the right side and the left side of which extend upwardrespectively to form a fixation joint 11″ for the pivot arm component 3″to pivotally connect to. The loading platform set 2″ includes a firstloading platform 21″ capable of horizontally load an object, and asecond loading platform 22″ connecting to the first loading platform 21″via the extension holder 23″ to form a height difference. The two sidesof the bottom of the first loading platform 21″ connect to an activejoint 211″ for the pivot arm component 3″ to connect to.

The pivot arm 3″ includes two first pivot arms 31″ and two second pivotarms 32″ located at two sides thereof respectively. One end of each ofthe first and second pivot arms 31″, 32″ connects to the fixation joint11″, and the other end of each of them connects to the active joint211″. The positions of the pivotal connection shafts can substantiallyform a parallelogram.

In order to keep the stability of the structure, the active joint 211″has a locking sheet 213″, and the locking sheet 213″ connects to theconnection board 212″ of the active joint 211″ by using three shafts asthe fixation points. In this way, the first and second pivot arms 31″,32″ can form the intersecting and overlapping status without interferingwith each other during the pivot operation, and both of them can keeppartially overlapping with each other during the pivot operation so asto reduce the accidents. The locking sheet 213″ can concentrate thestress on the pivotal connection point and fix the relative position, sothe loading platform set 2″ will not be unstable because the armsintersect with each other or due to the stress difference. Similarly,the fixation joint 11″ further includes a locking sheet 111″ forenhancing the stability between the fixation joint 11″, and the firstand second pivot arms 31″, 32″.

In the embodiment, the two sides are respectively installed with adamping positioning mechanism 4″, which majorly include an adjustabledamper 41″ and a switch 42″. One end of the adjustable damper 41″ isinstalled on the second pivot arm 32″ of the pivot arm component 3″, andthe other end thereof connects to the active joint 211″ via anadjustment component 12″. The switch 42″ connects to the adjustabledamper 41″ via a control cord 43″ to control the adjustable damper 41″to be the adjustable status or the locked status. The adjustmentcomponent 12″ mainly includes a first pivot seat 120″ and a lead screw121″. The first pivot seat 120″ is installed on the lead screw 121″, andthe adjustable damper 41″ connects to the first pivot seat 120″. Thelead screw 121″ can be installed in a slot way 122″ and the slot way122″ is fixed at the active joint 211″ for further fixation. The leadscrew 121″ can revolve to drive the first pivot seat 120″ to relativelymove, and then change the support angle of the adjustable damper 41″connecting to the first pivot seat 120″, such that the damping supportforse (vertical force component) of the adjustable damper 41″ providedfor the loading platform set 2″ can be adjusted so as to achieve balancewith the load and decrease the burden of the descending/ascendingoperation.

As shown in FIGS. 17 and 18, which show the mechanism is positioned atthe high position and the low position respectively. In actualoperation, when the switch 42″ is operated, the adjustable damper 411″can be adjusted to be the adjustable status (i.e. the adjustable damper41″ can freely extend or retract); at this time, the user can freelyoperate the loading platform set 2″ to ascend or descend so as to adjustit to the desired height; after the adjustment is done, the user canstop pressing the switch 42″, and then the adjustable damper 41″ returnsto the locked status (i.e. the adjustable damper 41″ cannot freelyextend or retract) in order to fix the loading platform set 2″ at thedesired height.

According to the previous embodiments, one end of the adjustable damper41″ can be freely and selectively to installed on one of the first pivotarm 31″ and the second pivot arm 32″ of the pivot arm component 3″, andthe other end thereof can freely and selectively connect to the loadingplatform set 2″ or the loading component 1″.

Further referring to FIGS. 19-23, which show the fourth embodiment ofthe present invention, the main structure comprises: a loading component5, a loading platform set 6, a pivot arm component 7 and a dampingpositioning mechanism 8. Therein, the loading component 5 is composed ofa guiding post 51, a revolver 52 and a retainer 53. The guiding post 51has its one end provided with a clamp 54 configured to hold an externalarticle or table and position the self-positionable lifting device withrespect to the article or table. The revolver 52 and the retainer 53 aremounted around the middle part of the guiding post 51, and the retainer53 is fixed below the revolver 52. With the retaining force from theretainer 53, the revolver 52 is rotatably positioned at the set altitudeon the guiding post 51. The revolver 52 has a fixation joint 521 and aninner pivot shaft 522, and a first pivot seat 523 is pivotally connectedto the inner pivot shaft 522.

The loading platform set 6 is composed of a first loading platform 61, asecond loading platform 62, a pivotable support 64 and a pivotalconnector 66. The first and second loading platforms 61 and 62 aremutually connected by means of an extension support 63, so that thefirst and second loading platforms 61 and 62 are parallel to each otherand have an altitudinal difference therebetween.

The pivotal connector 66 has an active joint 661 and a pivotal shaft 662parallel to the guiding post 51. The pivotable support 64 has its oneend connected to the first loading platform 61 (or the second loadingplatform 62). At the middle part of the pivotable support 64, aconnector 641 and an adjustable holder 651 are provided. The connector641 is pivotally mounted around the pivotal shaft 662, and theadjustable holder 651 is adjustablty fixed to the middle part of thepivotable support 64. The adjustable holder 651 is pivotally providedwith a mount 65 that is configured to hold an external device (such asan LCD).

In a feasible embodiment, the first loading platform 61 is pivotallyconnected to the terminal of the pivotable support 64 by means of afirst pivot 611. The extension support 63 may be combined with the firstloading platform 61. The second loading platform 62 is pivotallyconnected to the terminal of the extension support 63 by means of asecond pivot 621.

The pivot arm component 7 is composed of a first pivot arm 71 and asecond pivot arm 72 that are parallel to each other. The first andsecond pivot arms 71 and 72 each have one end pivotally connected to thefixation joint 521 of the loading component 5 by means of a E or F, andeach have an opposite end pivotally connected to the active joint 661 ofthe loading platform set 6 by means of a pin G or H. The correspondingends of the pins E, F, G and H jointly define a parallelogramic area.The first pivot arm 71 is provided with a second pivot seat 711.

In the present embodiment shown in the drawings, the first and secondpivot arms 71, 72 are telescoped, so as to eliminate the risk of mutualinterference therebetween in practical operation.

The damping positioning mechanism 8 is composed of an adjustable damper81 (that may be a gas cylinder with locking function) and a switch 82.The adjustable damper 81 is pivotally connected between the second pivotseat 711 of the first pivot arm 71 and the first pivot seat 523 of theloading component 5, and the adjustable damper 81 is connected to theswitch 82 by means of a control cord 83. The switch 82 may be placed atone side of the second loading platform 62 and may have an operatablepaddle 821. When the paddle 421 is operated, the switch 82 controls theadjustable damper 81 to allow it to extend or retract in response to anexternal force. When the paddle 821 is released, the adjustable damper81 locks itself from extending and retracting.

Referring to FIGS. 21, 22 and 24, according to the fourth embodiment ofthe present invention, during the positional adjustment, when the paddle821 is operation, the second loading platform 62 can be pushed orpressed at the same time by a user, so that the loading platform set 6drives the first and second links 71, 72 to rotate relatively.Throughout the process of the rotation, the imaginary line connectingthe pins G and H remains parallel to the imaginary line connecting thepins E and F (holding the parallelogramic area), so the loading platformset 6 is restricted to move forward/backward and upward/downward whileremaining parallel to the loading component 5. With the pivotal movementof the first link 71, the damper 81 receives force and is driven toextend or retract.

When the loading platform set 6 moves to a desire position, the user mayrelease the paddle 821, so that the adjustable damper 81 is locked andprevented from extending and retracting, making the loading platform set6 positioned. Thereby, even if the loading platform set 6 (the first andsecond loading platforms 61 and 62) receives external force (such asthat from a user's palms pressing the second loading platform 62 whenoperating a keyboard placed on the second loading platform 22), it isunlikely to have unintentional displacement, making its use moreconvenient.

In practical use, the second loading platform 62 be folded by pivotingit upward on the second pivot 621 (as shown in FIG. 21), and the firstloading platform 61 may also be folded by pivoting it upward on thefirst pivot 611 (not shown), thereby minimizing the space required forstoring the collapsed structure.

In the process that the first and second loading platforms 61 and 62 arepushed to move leftward (or rightward), with the pivotable support 64(i.e. the connector 641) that pivots with respect to the pivotalconnector 66, and the revolver 52 that pivots with respect to theguiding post 51, the first and second loading platforms 61 and 62 canremain facing forward (its initial orientation) without deviating withthe pivot arm component 7, further improving the convenient use of thepresent invention.

In a feasible embodiment, the inner pivot shaft 522 can be a lead screw,and the combination of which and the first pivot seat 523 can form theadjustment component for adjusting the damping support forse. The innerpivot shaft 522 can revolve to drive the first pivot seat 523 to moveupward and downward in order to change the support angle of theadjustable damper 81 connecting to the first pivot seat 523, such thatthe damping support forse of the adjustable damper 81 provided for theloading platform set 6 can be adjusted to achieve balance with the load,which can decrease the burden of the descending/ascending operation.Furthermore, as shown in FIGS. 25 and 26, an indicator mechanism 55 canbe provided to connect to the adjustment component, which includes anindicator 511 connecting to the first pivot seat 523 and can move upwardand downward. The indicator 551 has a front end 552 protruding outward,which can show the damping support forse for the user to observe.

To sum up, the mechanism of the present invention can be moreconvenient, strength-saving and of higher operation stability; besides,the mechanism can freely adjust the damping support forse according todifferent load requirements, so can significantly increase theconvenience in use. The present invention has been described withreference to the preferred embodiments and it is understood that theembodiments are not intended to limit the scope of the presentinvention. Moreover, as the contents disclosed herein should be readilyunderstood and can be implemented by a person skilled in the art, allequivalent changes or modifications which do not depart from the conceptof the present invention should be encompassed by the appended claims.

What is claimed is:
 1. A lifting mechanism with support function,comprising: a fixation joint; an active joint, connecting to a loadingplatform set; a pivot arm component, pivotally installed between thefixation joint and the active joint, and including a first pivot arm anda second pivot arm, wherein one end of the first pivot arm and one endof the second pivot arm are pivotally connected to the fixation joint,and the other end of the first pivot arm and the other end of the secondpivot arm are pivotally connected to the active joint; a relationposition of the first pivot arm, the second pivot arm, a pivot shaft ofthe fixation joint and a pivot shaft of the active joint substantiallyform a parallelogram, whereby the first pivot arm and the second pivotarm are able to pivot within a certain range, and the active jointdescends or ascends relative to the fixation joint; a dampingpositioning mechanism, including an adjustable damper and a switch,wherein one end of the adjustable damper is installed on the pivot armcomponent, and the other end of the adjustable damper connects to thefixation joint or the active joint via an adjustment component; and theadjustable damper is connected to the switch via a control cord, andable to be controlled by the switch to be an adjustable status or alocked status; the adjustable damper is able to extend or retract, andprovides a certain damping support forse during the adjustable status,so the active joint is able to pivot relative to the fixation joint viathe pivot arm component; the adjustable damper is able to fix an anglebetween the pivot arm component, and the active joint or the fixationjoint during the locked status for positioning; wherein the adjustmentcomponent includes a first pivot seat capable of relatively moving, andthe end of the adjustable damper pivotally connects to the first pivotseat, and a support angle of the adjustable damper is able to be changedby adjusting a position of the first pivot seat so as to adjust thedamping support forse provided from the adjustable damper to support theloading platform set.
 2. The lifting mechanism with support function ofclaim 1, wherein the end of the adjustable damper connects to the firstpivot arm or the second pivot arm via a second pivot seat.
 3. Thelifting mechanism with support function of claim 1, wherein theadjustment component further includes a lead screw, and the first pivotseat is mounted on the lead screw; when the lead screw revolves, thefirst pivot seat is able to move toward to lead screw.
 4. The liftingmechanism with support function of claim 3, wherein the adjustmentcomponent further connects to an indicator mechanism for displaying ameasurement of the damping support forse provided for the loadingplatform set.
 5. The lifting mechanism with support function of claim 4,wherein the indicator mechanism includes a gear set connecting to thelead screw; the gear set is able to revolve by being linked to the leadscrew, and display the measurement of the damping support forse providedfor the loading platform set via an opening externally exposed tooutside.
 6. The lifting mechanism with support function of claim 4,wherein the indicator mechanism includes an indicator connecting to thefirst pivot seat, and the indicator is able to move with the first pivotseat, and display the measurement of the damping support forse providedfor the loading platform set via a front end protruding outward.
 7. Thelifting mechanism with support function of claim 1, wherein the firstpivot arm and the second pivot arm pivotally connect to an innerposition and an outer position respectively via a plurality of shaftsleeves; the first pivot arm and the second pivot arm have lateral wallscapable of overlapping with each other, whereby the lateral walls areable to partially overlap with each other when the first pivot arm andthe second pivot arm are in operation.
 8. The lifting mechanism withsupport function of claim 7, wherein the active joint further includes aconnection board and a locking sheet, and the first pivot arm and thesecond pivot arm are pivotally installed between the connection boardand the locking sheet.
 9. The lifting mechanism with support function ofclaim 7, wherein the locking sheet is fixed on the connection board viathree points substantially form a triangle; the first pivot arm and thesecond pivot arm respectively pivotally connect to one of the threepoints.
 10. The lifting mechanism with support function of claim 1,wherein the fixation joint is fixed at a base, a clamping base or arevolver.
 11. The lifting mechanism with support function of claim 1,wherein the active joint connects to a platform or a pivot holder.